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Imagine that Kevin can instantly transport himself between Planet X and Planet Y. Which statement could be said about Kevin in this situation?

2 Answers

6 votes

Kevin’s weight may change between Planet X and Planet Y.

Mass is the amount of matter contained in an object. Gravity is Earth’s pull of a body towards its center.

Weight (W) is product of the mass (m) of the object and the force of gravity (g) acting on the object.

W = mg

The force of gravity may change between Plant X and Planet Y, and thus Kevin’s weight may change between Planet X and Planet Y.

User AWT
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5 votes
What are the choices ?

Without some directed choices, I'm, free to make up any
reasonable statement that could be said about Kevin in this
situation. A few of them might be . . .

-- Kevin will have no trouble getting back in time for dinner.

-- Kevin will have no time to enjoy the scenery along the way.

-- Some simple Physics shows us that Kevin is out of his mind.
He can't really do that.

-- Speed = (distance covered) / (time to cover the distance) .

If time to cover the distance is zero, then speed is huge (infinite).

-- Kinetic energy = (1/2) (mass) (speed)² .

If speed is huge (infinite), then kinetic energy is huge squared (even more).
There is not enough energy in the galaxy to push Kevin to that kind of speed.

-- Mass = (Kevin's rest-mass) / √(1 - v²/c²)

-- As soon as Kevin reaches light-speed, his mass becomes infinite.
-- It takes an infinite amount of energy to push him any faster.
-- If he succeeds somehow, his mass becomes imaginary.
-- At that point, he might as well turn around and go home ...
if he ever reached Planet-Y, nobody could see him anyway.
User John McClane
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